ObjectiveTo summarize the recent advances in the pathogenic mechanism of microorganisms and pancreatic cancer.MethodThrough the retrieval of relevant literatures, the recent progresses in the study of microorganism and pathogenesis of pancreatic cancer were reviewed.ResultsIn recent years, the potential role of intestinal microbiota in the pathogenic mechanism of pancreatic cancer had been studied. The studies found that the microbiome played an important role in the development of pancreatic cancer. Among them, the infections of Helicobacter pylori, oral pathogenic bacteria such as the Porphyromonas ginggivalis, Aggregatibacter actinomycetemcomitans and Phylum fusobacteria, and the changes of composition and diversity of intestinal microflora were closely related to the pancreatic cancer. The microorganisms induced the chronic inflammation and immune response through multiple pathways. The bacterial lipopolysaccharide stimulated the mutations in the KARS gene and mediated the inflammatory response by activating the nuclear factor-κB signaling pathway through Toll like receptor. The oral pathogenic microorganisms and Helicobacter pylori could also promote the cancer progression by secreting toxins that activated cancer-related signaling pathways.ConclusionsBacteria might be important carcinogens. These microorganisms promote development of cancer by causing chronic inflammation, activating cancer-related pathways, activating immune response, oxidative stress, and damaging DNA double strands.